Need help quick on carb problems.

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by 85 Shortbox, May 21, 2003.

  1. 85 Shortbox

    85 Shortbox 1/2 ton status

    Jan 24, 2002
    Likes Received:
    Grandville, Mi
    If I can't figure out #1 then #2 is my alternative.

    I can't get my quadrajet I recently swapped on to idle. It will fluxuate from 900-1500 rpm's. I checked all over and it isn't a vacum leak, I believe it is something to do with the choke, or perhaps maybe even the timing. I am running a big cam so that isn't helping a whole lot. Also when I try to drive it while it is fluxuating there is no power, and I can't wind up the motor at all.

    I am going to try and run a demon carb on my truck, problem is it only has 2 vacum ports. 1 for the advance and one for the brakes. I am wondering if I can put a T in the brake hose and connect the pcv valve that way or if it will depleet my vacum too much and affect my brakes.

    Thanks guys.
  2. dyeager535

    dyeager535 1 ton status Premium Member

    Dec 13, 2000
    Likes Received:
    Roy WA
    What are the engine specs? With too little vacuum, the primaries won't stay "shut".

    Choke isn't very complicated, is the blade wide open when it's warm? If idle is fluctuating because of the choke, you'll see it in the choke blade, likely moving. That could be why you can't wind the motor up, the secondaries would stay locked shut without the choke open.

Share This Page